an.andi<

Theorem.

Arguments:

phi (pr), psi (pr), chi (pr),

Assertions:

((phiwedge(psiwedgechi))leftrightarrow((phiwedgepsi)wedge(phiwedgechi)))

Proof:

Hyp Ref Line Expr
anidm1((phiwedgephi)leftrightarrowphi)
1bicomi2(phileftrightarrow(phiwedgephi))
2bi.bldan<3((phiwedge(psiwedgechi))leftrightarrow((phiwedgephi)wedge(psiwedgechi)))
4anass4(((phiwedgephi)wedge(psiwedgechi))leftrightarrow((phiwedgepsi)wedge(phiwedgechi)))
3, 4bitr5((phiwedge(psiwedgechi))leftrightarrow((phiwedgepsi)wedge(phiwedgechi)))